The health watchdog has received complaints of abuse and neglect of foster children.
The regulator also got a complaint about the management of a sexual allegation against a child.
The details have been released under the Freedom of Information Act.
There are almost 5,500 children in foster care across the country.
The Health Information and Quality Authority received 36 ‘concerns’ about their care between January 2019 and this February.
According to one complaint, a young person was neglected by Tusla and at risk of abuse because of a lack of counselling and therapy.
Another person said they were very dissatisfied with the management of a serious allegation against foster carers.
Another complaint relates to a sexual allegation by one child against another not being dealt with properly, and one child remaining at risk.
Other complaints involve abuse and alcohol misuse in foster homes, birth parents not having enough access to their children, along with a child with special needs being without a social worker for six months.
Tusla said there will always be times when people are not satisfied with their experiences.
The agency says it wants to hear this feedback as it helps to look into individual concerns, find resolutions and looking into areas where improvements may be necessary.